Hello, This one has been bugging me for a while. When you drive a car past parked cars that are somewhat close, with the window down, there is a rhythmic whooshing sound. This sounds very much like numerous dopplershifts, but I have difficulty seeing it as a doppler shift because the parked cars are not emitting any sound. My current guess is that the speed of the moving car causes the air between the moving and parked vehicle to be temporarily disturbed, lowering its pressure and causing the noise. Is it a doppler shift or something else?